title: Alginate beads as a storage, delivery and containment system for genetically modified PCB degrader and PCB biosensor derivatives of Pseudomonas fluorescens F113.
abstract: OBJECTIVE
  Pseudomonas fluorescens F113Rifpcb is a genetically engineered rhizosphere bacterium with the potential to degrade polychlorinated biphenyls (PCBs). F113Rifpcbgfp and F113L::1180gfp are biosensor strains capable of detecting PCB bioavailability and biodegradation. The aim of this paper is to evaluate the use of alginate beads as a storage, delivery and containment system for use of these strains in PCB contaminated soils.
  
  
  RESULTS
  The survival and release of Ps. fluorescens F113Rifpcb from alginate beads were evaluated. Two Ps. fluorescens F113-based biosensor strains were encapsulated, and their ability to detect 3-chlorobenzoate (3-CBA) and 3-chlorobiphenyl (3-CBP) degradation in soil was assessed. After 250 days of storage, 100% recovery of viable F113Rifpcb cells was possible. Amendments to the alginate formulation allowed for the timed release of the inoculant. Encapsulation of the F113Rifpcb cells provided a more targeted approach for the inoculation of plants and resulted in lower inoculum populations in the bulk soil, which may reduce the risk of unintentional spread of these genetically modified micro-organisms in the environment. Encapsulation of the biosensor strains in alginate beads did not interfere with their ability to detect either 3-CBA or 3-CBP degradation. In fact, detection of 3-CBP degradation was enhanced in encapsulated biosensors.
  
  
  CONCLUSIONS
  Alginate beads are an effective storage and delivery system for PCB degrading inocula and biosensors.
  
  
  CONCLUSIONS
  Pseudomonas fluorescens F113Rifpcb and the F113 derivative PCB biosensor strains have excellent potential for detecting and bioremediation of PCB contaminated soils. The alginate bead delivery system could facilitate the application of these strains as biosensors.
authors.affiliation: Department of Science and Health, Institute of Technology Carlow, Carlow, Ireland.
authors.forename: B
authors.initials: B
authors.lastname: Power
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.forename: K J
authors.initials: KJ
authors.lastname: Germaine
authors.forename: D
authors.initials: D
authors.lastname: Ryan
authors.forename: D
authors.initials: D
authors.lastname: Brazil
authors.forename: D N
authors.initials: DN
authors.lastname: Dowling
mesh_terms: D000464:Alginates / Q000737:chemistry*; D001673:Biodegradation, Environmental; D015374:Biosensing Techniques; D001713:Biphenyl Compounds / Q000302:isolation & purification / Q000378:metabolism; D002723:Chlorobenzoates / Q000302:isolation & purification / Q000378:metabolism; D005818:Genetic Engineering; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D000455:Medicago sativa / Q000382:microbiology; D008863:Microspheres; D011078:Polychlorinated Biphenyls / Q000302:isolation & purification* / Q000378:metabolism; D011551:Pseudomonas fluorescens / Q000254:growth & development / Q000378:metabolism*; D058441:Rhizosphere; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D000464:Alginates; D001713:Biphenyl Compounds; D002723:Chlorobenzoates; D006603:Hexuronic Acids; D012989:Soil Pollutants; C036427:3-chlorobenzoic acid; D020723:Glucuronic Acid; D011078:Polychlorinated Biphenyls; C034280:3-chlorobiphenyl